Sometime near the year 2050, the world’s population will grow beyond 10 billion. And there is no guarantee the world’s denizens will practice good hygiene. Even in high-hygiene countries like the UK, one in three women go several days without bathing.

“Stink can be reduced,” says Blade Cavanaugh, founder of Stinkeroo, an app that allows users to inform someone anonymously that he or she has body odour. “Knowing you stink – problem recognition – is the first step to eliminating the problem.” Cavanaugh got the idea while working at the South Pole, helping to populate the area with polar bears. “We had plenty of showers at the Amundsen-Scott station, but there was this one guy who just wouldn’t use them. I just had this epiphany.”

Stinkeroo, Cavanaugh’s app, allows anyone to send “stinkeryous” to people who stink, an unsubtle alert about body odour. “This app isn’t just some elitist rant,” says Cavanaugh. “It actually solves the problem.” Those who accumulate three stinkeryous are automatically sent a coupon for a free shower at a public bath. At four stinkeryous they get a coupon to have one change of clothes laundered.

Although odoriferous people create problems everywhere, the Stinkeroo team is banking on the app finding a home on public transportation. “It’s not just about the guy in the back of the bus who’s shat himself,” says Cavanaugh. “Stinkeroo is a public health app that fights halitosis, flatulence and bromhidrosis.” Stinkeroo is currently under rigorous test aboard public transport in pilot markets (“low-stink Frankfurt” and “high-stink Kyiv,” says Cavanaugh).

The technologies behind the app have been called “bluetooth override” or “forced SMS,” reportedly developed by cyber warriors at Estonia’s Cyber Defence Centre. It enables a message to be sent to another telephone regardless of whether the receiver has given permission.

Cavanaugh refuses to comment on rumours that the CIA and World Health Organization have signed on as customers. “I could tell you more, but you would have to sign the most draconian NDA of your life, and even then you still couldn’t write about it.”

Stinkeroo is tight-lipped about financing, but industry insiders say its stinker- you coupons are heavily funded by local bathhouses and dry cleaners. A source close to Stinkeroo, who did not have authority to speak on the company’s behalf, says first-round funding was in large part underwritten by a grant from the Koch brothers. Rumours that Amal Clooney is serving in an advisory capacity are also unconfirmed.

Cavanaugh is sensitive to criticism that the app represents nothing more than an elitist rant. “I guess you could level that criticism at most of the IT world,” he says. “It’s mostly just solutions chasing problems. But the odour is an outward sign of bacteria, and dealing with bacteria makes the world a better place.”